Consolidated Statements of Changes in Shareholders' Equity (unaudited) - USD ($) $ in Thousands		Total	Common Stock		Retained Earnings	Accumulated Other Comprehensive (Loss) Gain
Beginning balance (in shares) at Dec. 31, 2017	[1]		16,885,615
Beginning balance at Dec. 31, 2017		$ 101,352	$ 57,880		$ 44,182	$ (710)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		230				230
Dividends payable		(1,520)			(1,520)
Restricted stock units released (in shares)			13,000
Restricted stock units released		0
Stock-based compensation expense		291	$ 291
Net Income		3,156			3,156
Ending balance (in shares) at Mar. 31, 2018	[2]		16,898,615
Ending balance at Mar. 31, 2018		103,509	$ 58,171		44,152	1,186
Beginning balance (in shares) at Dec. 31, 2017	[1]		16,885,615
Beginning balance at Dec. 31, 2017		101,352	$ 57,880		44,182	(710)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends payable		(1,690)
Net Income		10,068
Ending balance (in shares) at Sep. 30, 2018	[3]		16,903,290
Ending balance at Sep. 30, 2018		107,046	$ 58,472		47,852	722
Beginning balance (in shares) at Mar. 31, 2018	[2]		16,898,615
Beginning balance at Mar. 31, 2018		103,509	$ 58,171		44,152	1,186
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		(304)				(304)
Dividends payable		(1,519)			(1,519)
Restricted stock units released (in shares)			3,003
Restricted stock units released		0
Stock-based compensation expense		138	$ 138
Net Income		3,392			3,392
Ending balance (in shares) at Jun. 30, 2018	[4]		16,901,618
Ending balance at Jun. 30, 2018		105,216	$ 58,309		46,025	882
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		(160)				(160)
Dividends payable		(1,691)			(1,691)
Restricted stock units released (in shares)			1,672
Restricted stock units released		0
Stock-based compensation expense		163	$ 163
Net Income		3,518			3,518
Ending balance (in shares) at Sep. 30, 2018	[3]		16,903,290
Ending balance at Sep. 30, 2018		107,046	$ 58,472		47,852	722
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		(48)				(48)
Dividends payable		(1,859)			(1,859)
Restricted stock units released (in shares)			43,332
Restricted stock units released		0
Stock-based compensation expense		152	$ 152
Net Income		$ 3,949			3,949
Ending balance (in shares) at Dec. 31, 2018		16,946,622	16,946,622	[5]
Ending balance at Dec. 31, 2018		$ 109,240	$ 58,624		49,942	674
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		(284)				(284)
Dividends payable		(1,869)			(1,869)
Restricted stock units released (in shares)			2,500
Restricted stock units released		0
Stock-based compensation expense		99	$ 99
Net Income		4,007			4,007
Ending balance (in shares) at Mar. 31, 2019	[1]		16,949,122
Ending balance at Mar. 31, 2019		$ 111,193	$ 58,723		52,080	390
Beginning balance (in shares) at Dec. 31, 2018		16,946,622	16,946,622	[5]
Beginning balance at Dec. 31, 2018		$ 109,240	$ 58,624		49,942	674
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends payable		(1,866)
Net Income		$ 12,276
Ending balance (in shares) at Sep. 30, 2019		16,953,744	16,953,744	[6]
Ending balance at Sep. 30, 2019		$ 115,210	$ 58,896		56,619	(305)
Beginning balance (in shares) at Mar. 31, 2019	[1]		16,949,122
Beginning balance at Mar. 31, 2019		111,193	$ 58,723		52,080	390
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		(182)				(182)
Dividends payable		(1,865)			(1,865)
Restricted stock units released (in shares)			4,622
Restricted stock units released		0
Stock-based compensation expense		95	$ 95
Net Income		4,097			4,097
Ending balance (in shares) at Jun. 30, 2019	[6]		16,953,744
Ending balance at Jun. 30, 2019		113,338	$ 58,818		54,312	208
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)		(513)				(513)
Dividends payable		(1,866)			(1,866)
Restricted stock units released		0
Stock-based compensation expense		78	$ 78
Net Income		$ 4,173			4,173
Ending balance (in shares) at Sep. 30, 2019		16,953,744	16,953,744	[6]
Ending balance at Sep. 30, 2019		$ 115,210	$ 58,896		$ 56,619	$ (305)

[1] Excludes 46,511 unvested restricted shares

[2] Excludes 116,597 unvested restricted shares

[3] Excludes 78,508 unvested restricted shares

[4] Excludes 78,508 unvested restricted shares

[5] Excludes 59,217 unvested restricted shares

[6] Excludes 55,713 unvested restricted shares